let V, W be non empty ModuleStr over INT.Ring ; for f being FrFunctional of V
for v being Vector of V
for w being Vector of W holds (FrFormFunctional (f,(0FrFunctional W))) . (v,w) = 0. INT.Ring
let f be FrFunctional of V; for v being Vector of V
for w being Vector of W holds (FrFormFunctional (f,(0FrFunctional W))) . (v,w) = 0. INT.Ring
let v be Vector of V; for w being Vector of W holds (FrFormFunctional (f,(0FrFunctional W))) . (v,w) = 0. INT.Ring
let y be Vector of W; (FrFormFunctional (f,(0FrFunctional W))) . (v,y) = 0. INT.Ring
set 0F = 0FrFunctional W;
set F = FrFormFunctional (f,(0FrFunctional W));
thus (FrFormFunctional (f,(0FrFunctional W))) . (v,y) =
(f . v) * ((0FrFunctional W) . y)
by HDef10
.=
(f . v) * (0. INT.Ring)
by FUNCOP_1:7
.=
0. INT.Ring
; verum